Case definition of patients with snakebite envenoming
| No envenoming | Patients with no local or systemic signs or symptoms |
| Mild envenoming | Local oedema in one or two segments, pain at the bite site, absence of systemic signs or symptoms. |
| Moderate envenoming | Oedema in three segments, local haemorrhage. Systemic symptoms (bleeding, hypotension) and blood clotting test alterations |
| Severe envenoming | Oedema extending to the whole limb, local haemorrhage with necrosis, severe hypotension, blood clotting alterations, systemic bleeding and, in some cases, acute kidney injury. |